chore(i18n): add missing colon after 'duration'

Author: qwqcode

SubRenamer/Assets/Lang/en-US.axaml

@@ -134,7 +134,7 @@ It can be modified to: "[Steins;Gate][$$]*.sc.ass"</system:String>
     <system:String x:Key="App.Strings.SaveFileDialogTitle">Save File</system:String>
     <system:String x:Key="App.Strings.SubSyncTasksComplete">All tasks have been completed.</system:String>
     <system:String x:Key="App.Strings.SubSyncTasksFail">Task execution failed.</system:String>
-    <system:String x:Key="App.Strings.SubSyncTasksDuration">Duration</system:String>
+    <system:String x:Key="App.Strings.SubSyncTasksDuration">Duration:</system:String>
     <system:String x:Key="App.Strings.SubSyncBinDownloadTitle">FFsubsync automatic timeline synchronization</system:String>
     <system:String x:Key="App.Strings.SubSyncBinDownloadDesc">Downloading FFsubsync...</system:String>
     <system:String x:Key="App.Strings.SubSyncBinDownloadDone">FFsubsync download successful</system:String>

SubRenamer/Assets/Lang/ja-JP.axaml

@@ -134,7 +134,7 @@
     <system:String x:Key="App.Strings.SaveFileDialogTitle">ファイルを保存</system:String>
     <system:String x:Key="App.Strings.SubSyncTasksComplete">すべてのタスクが完了しました。</system:String>
     <system:String x:Key="App.Strings.SubSyncTasksFail">タスクの実行に失敗しました。</system:String>
-    <system:String x:Key="App.Strings.SubSyncTasksDuration">処理時間</system:String>
+    <system:String x:Key="App.Strings.SubSyncTasksDuration">処理時間:</system:String>
     <system:String x:Key="App.Strings.SubSyncBinDownloadTitle">FFsubsync の自動タイムライン同期</system:String>
     <system:String x:Key="App.Strings.SubSyncBinDownloadDesc">FFsubsync をダウンロードしています...</system:String>
     <system:String x:Key="App.Strings.SubSyncBinDownloadDone">FFsubsync のダウンロードに成功しました</system:String>

SubRenamer/Views/SettingsWindow.axaml

@@ -98,6 +98,9 @@
                     </StackPanel>
                 </StackPanel>
 
+                <!-- Middle Separator -->
+                <Border Grid.Column="1" BorderThickness=".5" Width="1" BorderBrush="#D2D4D5" Margin="15,0" />
+                
                 <!-- Right Column -->
                 <StackPanel Grid.Column="2">
                     <CheckBox IsChecked="{Binding FileClsExtAppendEnabled}" Content="{DynamicResource App.Strings.SettingsFileFormatExtension}" />